Compound angular ejection system



Jan. 31, 1961 c. A. BROWN COMPOUND ANGULAR EJECTION SYSTEM Filed Sept.5, 1957 4 Sheets-Sheet 1 INVENTOR Charles A. Brown ATT EY Jan. 31, 1961c. A. BROWN 2,969,569

COMPOUND ANGULAR EJECTION SYSTEM Filed Sept. 5, 1957 4 Sheets-Sheet 2INVENTOR Charles A. Brown BY ma? 4a A NEY Jan. 31, 1961 c. A. BROWNCOMPOUND ANGULAR EJECTION SYSTEM Filed Sept. 5, 1957 4 Sheets-Sheet 5 Ii I m lNVE NTOR Charles A. Brown BY We? 1 A ORNEY United States PatentCOMPOUND ANGULAR EJECTION SYSTEM Charles A. Brown, Sylvauia, Ohio,assignor to National Lead Company, New York, N.Y., a corporation of NewJersey Filed Sept. 5, 1957, Ser. No. 682,216

7 Claims. (CI. 22-92) This invention relates to die .casting, and moreparticularly to an improved form of die assembly.

Die casting lends itself readily to the production of parts having manydifferent and often very complex shapes. Some shapes require a verycomplex system of coring for successful reproduction and frequently thewithdrawal of cores or die segments from such castings presents a verydiflicult problem.

The angular ejector is a well known device used in die casting dies towithdraw cores and die segments from the casting coincidentally with theejection of the casting from the die and is actuated by the ejectormovement. This device is usable only when the cores or die segments canbe withdrawn at an angle of 90 with the direction of the ejectormovement. 1

The compound angular ejector is a device-that will withdraw cores or diesegments from the-casting .at angles other than 90 with the direction ofejection and is operated coincidental with and by the ejection movement:This, as far as is known, has never been accomplished before.

The hereinafter described die assembly and system of compound angularejection was devised to facilitate'the release ,of castings withcomplicated undercuts. Byuse of this system, either or both withdrawingangles may be varied to change the resultant movement of diefsegments orcores relative to the movement of the casting during ejection. r

It is therefore an object of this invention-to provide ,an improved formof die assembly incorporating oneror. more relatively movable segmentsor cores in which.,.the movement is so controlled as to withdraw thesegments in the proper angular relationship with respect to the castingso that the segments will clear the casting and no interference will, beencountered during withdrawal.

Another object of this invention is to .providean int-i proved form ofdie assembly including one or more rela-.

Patented Jan. 31, mm

Other and more specific objects will become apparent in the followingdetailed description of a typical form of die illustrating the presentinvention, and the accompanying drawings, wherein:

Fig. l is a plan view of the ejector die half with the compoundangularly movable segments in closed position;

Fig. 2 is a similar view of the same die half with the movable segmentsin opened position;

Figs. 3 and 4 are elevational sectional views taken on the lines 3-3 and4-4 in Figs. 1 and 2 respectively;

Figs. 5 and 6 are internal views of one of the movable die segmentstaken on lines 5-5 and 66 in Figs. 3 and 4 respectively. The relativerelationship of parts in the specific form of the die assembly shown inthe drawings for the purpose of illustration can be most clearly seenfrom a study of Figs. 3 and 4, wherein the reference numeral 10designates the cover die and the numeral 20 designates the ejector diewhich is comprised of ejector plate 70, holding block or housing 30,guide block 50, movable die segments 40, and core 80.

The ejector die 20 is mounted onto the sliding plate (not shown) of thedie casting machine. This die assembly includes in the specific formshown a holding block 30 composed of a pair of plates 32 and 34 rigidlysecured together and provided with tapered depressions 35 within whichthe movable die segments 40 are nested when the assembly is 'in theclosed position. Also included in this die assembly is core 80 whichimparts to the castings its interior configuration. Attached to thesloping wall of the depression are one or more pairs of guide bars 36arranged in spaced relationship, as will be seen most clear-1y in Fig.'1, so that the keyway 38 will be provided between such pair of bars.This keyway 38 is of T-slot configuration and is adapted to receive acorresponding key member 42 which is provided on the movable die segment40. v

The inner face of movable die segment 40 is of such configuration as toprovide a portion of the die cavity 60 and when the die assembly isclosed, as is shown in Fig. 3, the said movable die segments areintimately engaged along their opposite side faces with the mating sidefaces ofithe holding block depression so as to form a complete diecavity;

.In' addition'to being slidably mounted and guided by the keyedinterengagement between the die segments 40 and the holding block plate32, each movable die segtively movable die segments, each forming aportion of the die cavity, and in which the die segments are con-'strained from movement from the die cavity along paths which areseparately inclined for each such segment.

- A further object of this invention is to providean improved'form ofdie assembly to be used for casting com.-

plex forms without the use of individually operated slides for undercutportions in which the die includes one or more compound angularlywithdrawing segments adapted for, movement both angularly and laterallyfrom the casting. i p j H Another object of this invention is toprovidean improved die assembly incorporating a die housing,-and oneorinor'e separate die segments, within which a guide block is movableand upon which the die segments are also movably mounted such thatmotion of the block imparts a compound angular movement to the diesegments with respect to the casting, in accordance with the manner ofmounting these segments both on the housing and on the guide block. w

ment is additionally provided with a key member 44 which is slidablyinterengaged with the guide plate 52 fixed to the inclined upper surfaceof guide block 50. The. guide block 50 is guided in the holding blockdepression 35 by means of core rigidly mounted in the holding block.

When the parts are in the closed position, as is shown in Fig. 3, thecover die 10 is engaged against the front face of ejector die 20, thusforming, as the name implies, a cover for the die cavity. Thus, the diecavity 60 is defined or bounded by the inner faces of movable diesegments 40, the inner face of plate 32 or holding block 30,.cover die10 and core 80. The cover die is provided with an injection hole 12through which the molten metal is injected into the die cavity 60.

The ejector plate 70 is disposed to the rear of holding block 30 and hasprovided thereon connecting rods 72 projecting through the back plate 34of the holding block 30 and engaged as by the threaded connection shownto guide blockr50. The ejector plate also has provided thereon ejectorpins 74, projecting through the back plate 34 of the holding block 30,which eject the casting from the die cavity as the die is moved to theopen position.

After the molten metal has been injected and allowed a r q to solidify,with the die parts in the position of Figs. 3

and 5, the ejector die 20 is moved away from the cover die It and atthis time, the solidified sprue will remain with the casting. Thecasting cannot, of course, move relative to the ejector die componentssince it is interlockingly engaged by the compoundly movable segments.After the ejector die has been moved to its open position, as is shownin Fig. 4-, the ejector plate 70 is actuated by a hydraulic cylinder orother suitable means (not shown) until the stop pin 76 thereon engagesthe back surface of the holding block 30. Due to this movement of theejector plate 70, the connecting rods 72 will move the guide block 50toward the cover die to the position shown in Figs. 4 and 6 and theejector pins 74 will at the same time move in the same direction.Simultaneously, the casting 94) will be moved since-it is supportedduring the initial movement by a portion of the movable die segments 48and during the remainder of the movement by ejector pins 74. At the sametime, the movable die segments 40 will have a compound motion withrespect to the casting by virtue of the inclinations of the keyways onthe inner surface of the holding block depression 35 and on the innersurface of guide block 50. in other words, the movable die segments 40,being moved forward with the guide blocks 50, retreat from the center ofthe core 8%) in the direction determined by their lateral keyways 52 andat the same time they are being moved outwardly from the axis by virtueof the diverging relation of the keyways 38. The resultant motion of thedie segments 40 relative to the casting is a composite motion asafforded by the angularity of the two keyway systems. This compositemotion not only wtihdraws the segments laterally away from the casting,but moves the segments at an angle to the perpendicular so that the diesegments will withdraw from undercuts in the casting, such as arev shownat the axial faces of the flanged cylinder used as an example in thedrawings. The composite motion effects a simultaneous lateral expansionof the die segments and an axial movement of the die segments withrespect to the casting. The axial movement of the casting is greaterthan the axial component of movement-of the die segments because of thedownward slope of the keyways 52.

In the particular example shown, the compound motion of the die segmentswith respect to the casting will be a lateral outward movement and anangularly back? ward movement, as will be readily apparent. Of course,the particular inclination of the two aforementioned key way systemswill determine the overall relative motion between the die segments 49and the casting. That is to say, the inclination of the keyway system onthe inner surface of holding block depression 35 controls the rate oflaterally outward movement of the movable die segment, whereas theinclination of the keyway system on the inner surface of guide block 50determines the angular rate of withdrawal with respect to thelongitudinal axis of the casting, the two motions being interdependent.The inclination of the keyway system 52 on the guide block directs themovement of the die segment 40 with a component perpendicular to thedirection of movement of the casting and with a component parallel tothe direction of movement of the casting, not merely per pendicular tothe direction of such movement, which would not permit a withdrawal ofthe die segment from an undercut in the casting.

After the casting has been removedfrom the ejector die, the latter isclosed by backward movement of the ejector plate 70. The movementsperformed in the opening of the die as described above, are now reversedwith the guide block 50 and die segments 40 being returned to theiroriginal interfitting positions. With the ejector die closed against thecover die 10, the machine is ready to make the next casting.

The compound guided movements of the movable die segments may bearranged to separate the diesegments in any desired relative angulardirection and with any desired axial movement thereof with respect tothe casting, depending upon the particular shape of the casting. Manycomplex mechanical castings, previously necessitating a complex systemof special cores, may be easily produced in accordance with theteachings of this invention.

As previously mentioned, the angular disposition and directions of thekeyways is dependent upon the shape and peculiarities of the particularobject to be cast and the particular 'angularity, direction and relativerelationship of the keyways shown in the drawings and need notnecessarily prevail. Alsothe number of such movable die segments mayvary from one segment, necessary to impart the desired configuration toa portion of the casting, to a multiplicity of such segments which mayform, when closed, the entire peripheral configuration of the casting.Broadly speaking, the essence of this invention resides in the compoundangular movement of separable die members so as to accommodate for castshapes having projecting or undercut portions,

Although in the specific illustration shown, the die segments which arerestrained to a compound angular movement are a part of the die cavityforming the exterior surface of the casting, it is contemplated that thesame principal may be employed to form undercut portions on the interiorof the casting. In order to accomplish this, the compoundly movablesegments would be keyed to and form a part of the core of the die whichimparts the internal configuration to the casting and would moveangularly toward the center of the die cavity rather than angularly awayfrom it as the ejector plate is moved toward the ejector die.

In order to avoid a multiplicity of claims and the use of alternatives,the claims are worded and directed as to specifically mention the use ofthe compoundly movable die segments in the housing portion of the dieassembly. By the substitution of the word core for housing and the ideaof movement toward the center of the cavity rather than outwardlytherefrom, the claims apply equally as well to the employment of movabledie segments in the core portion of the die assembly. It is, therefore,the intent that both conceptions are understood to be included in thefollowing claims.

I claim:

1. A compounded ejection die comprising a die housing portion, at leastone movable die portion closely interfitted with the die housing portionand together with said housing portion forming a die cavity, means forejecting a casting from the die cavity, a guide block resting on theback plate of said housing portion and a cover die fitted over the openend of said die cavity and having a sprue for injection of the moltenmetal for the casting, an outwardly extending key and keyway between themovable die portion and said guide block for determining the relativedirection of retraction of said movable portion from the casting, saidkey and keyway extending outwardly at an angle other than degrees withrespect to the direction in which a casting is ejected, anotheroutwardly and angularly extending key and keyway between the movableportion and said housing portion for determining the extent of suchwithdrawal upon effecting relative movement of said guide block, andmeans for effecting such relative. movement of said guide blockcoincidental with ejection of the casting, the direction of retractionof the movable portion being at an angle of less than 90 with respect tothe direction of ejection of the casting;

2. A die as defined in claim 1, said means for effecting relativemovement of the guide block including an ejector plate having at leastone push rod slidably extending through bores in the rear of saidhousing portion and being fixed at their terminal ends to said guideblock,

and a plurality of short pins of equal length spaced about said ejectorplate between said push rods to provlde a stop for said ejector plateagainst the rear of said housing portion when said die segments areopened.

3. In a die casting machine, a die assembly including an ejector plateand a cover die and ejector die forming a die cavity, said ejector diecomprising a die housing having a recess therein, at least one movabledie segment nested within said recess and forming a part of the diecavity, and a guide block fixedly attached to said ejector plate andmovable therewith, a first means connected to said die segment formoving it axially outwardly of said recess, a second means slidablymounting the outer edge of said die segment upon an angular surface ofsaid housing whereby said die segment is moved laterally outwardly fromsaid recess as it is moved axially outwardly of the recess, and a thirdmeans for ejecting a casting formed within the die cavity axiallyoutwardly from the die cavity, said first means comprising a key memberon the die segment slidably engaged with a keyway in said guide block,said key member and keyway extending at an angle other than 90 degreeswith respect to the direction of ejection of a casting, said secondmeans comprising a key member on the outer edge of the die segmentslidably engaged with a keyway in an angular surface of said housing,said third means comprising ejector pins movable by said ejector platesuch that a constant relationship is maintained between the ejector pinsand the guide block, said first, second and third means cooperating tocause the movable die segment to be withdrawn from the casting at anangle of less than 90 to the direction of ejection of the casting fromthe die.

4. In a die casting machine, a core, a plurality of movable die segmentscooperating with said core to define a die cavity, ejector plate meansboth for lineally moving a casting ofi said core and for impartingmotion to said die segments, and guide means for directing the movementof said die segments away from said core in a direction having acomponent parallel to the direction of movement of the casting and acomponent perpendicular to the direction of movement of the casting, themagni' tude of the former component being less than the magnitude of themovement of the casting and more than any magnitude of movement of saidcore.

5. In a die casting machine, a core, a plurality of movable die segmentscooperating with said core to define a die cavity, a holding blocksurrounding said movable segments, a guide block for each of saidmovable segments, means for lineally moving a casting 011 said core,means for moving said guide blocks parallel to the direction of movementof the casting, first guide means associated with said die segments andsaid holding block for guiding said die segments in a divergingdirection with respect to the direction of movement of the casting, andsecond guide means associated with said die segments and said guideblocks, said second guide means being formed to guide said die segmentsin a direction having a component perpendicular to the direction ofmovement of the casting and a component parallel to the direction ofmovement of the casting.

6. In a die casting machine, a core, a plurality of movable die segmentscooperating with said core to define a die cavity, a holding blocksurrounding said movable segments, a guide block for each of saidmovable segments, means for lineally moving a casting ofi said core,means for moving said guide blocks parallel to the direction of movementof the casting, first guide means associated with said die segments andsaid holding block for guiding said die segments in a divergingdirection with respect to the direction of movement of the casting, andsecond guide means associated with said die segments and said guideblocks, said second guide means being formed to guide said die segmentsin a direction having a component perpendicular to the direction ofmovement of the casting and a component opposite to the direction ofmovement of the casting.

7. In a die casting machine, a plurality of movable die segments atleast partially defining a die cavity, a holding block surrounding saidmovable segments, a guide block for each of said movable segments, meansfor lineally moving a casting away from the die cavity, means for movingsaid guide blocks parallel to the di rection of movement of the casting,first guide means associated with said die segments and said holdingblock for guiding said die segments in a diverging direction withrespect to the direction of movement of the casting, and second guidemeans associated with said die segments and said guide blocks, saidsecond guide means being formed to guide said die segments in adirection having a component perpendicular to the direction of movementof the casting and a component opposite to the direction of movement ofthe casting.

References Cited in the file of this patent UNITED STATES PATENTS1,475,032 Shrum et al. Nov. 20, 1923 1,715,418 Langenberg June 4, 19291,776,888 Clark Sept. 30, 1930 2,272,718 MacLagan et al Feb. 10, 19422,292,593 Amigo Aug. 11, 1942 2,304,899 Dupre Dec. 15, 1942 2,464,051Morin Mar. 8, 1949 2,529,091 Lester Nov. 7, 1950

